marilynm

Is she Oriental? If so, maybe ABsub? Other possibility is group A with missing isoagglutinin. So, are you going to get ABO genotyping done? Marilynm PS On another note, are you going to aabb in Baltimore? I am cochairing a RAP session with John Moulds on tube, gel and solid phase and am encouraging everyone to think about presenting or attending.

In a hospital, maybe you have a unit that is returned to the transfusion service that was not all used up, or some left from splitting for a baby, etc. Expired units can be used for adsorption. The problem is that you need to type the units for Rh, Kell, Kidd, Duffy and Ss (only for Rh, Kell and Kidd if you use enzyme treated cells). You may not have the typing reagents, or enzymes, if you are a small lab. However, with that wonderful explanation Malcolm gave, you at least will understand the technique and why it might take your reference lab a day for two to get blood for your patient!! marilyn m PS Absorption is still used it we want to remove a certain antibody from a plasma, and this is accomplished by adsorbing it with a cell having the corresponding antigen.

As always, different techniques are out there. Both Solid phase and gel are very sensitive for picking up Rh Immune globulin anti-D. We do a manual gel panel and get the Rh Immune globulin history and make the comment likely due to the injection. We do not send ours out and do not do a tube panel. Would love to have you all come to the aabb RAP session on Family Fued: differences in gel, glass bead, solid phase and tube, and share your cases with everyone, if you are attending the meeting. marilynm

PS: I forgot to mention that the title of the 1996 Letter to the Editor was Autoadsorptions for the detection of alloantibodies-should polyethylene glycol be used? marilynm

From an "old timer", the original reference to PEG for autoadsorption was a Letter to the editor of Transfusion 1995;35:713 by Yew Wah Liew entitled Polyethylene glycol in autoadsorption of serum for detection of alloantibodies. The first reference for weak alloantibodies being not detected using this technique, and a reply by Yew Wah was another Letter to the Editor in Transfusion 1996;36:384 by Kayla Champagne and Marilyn K. Moulds. It seems it took some years before anyone listened to Kayla and myself about the missing of weak antibodies by this technique and published their own data. Were these antibodies clinically significant? Ours was an anti-K. A little trivia for the day. marilynm

If tube technique is so "outdated' or archaic, or whatever, why do almost all the 58 IRL (Immunohematology Reference Laboratories), which is all but 9, in the US, use TUBE technique for all their testing!! Sorry, but I think tube testing is here to stay, even if it is not the main technique used in a lab. Marilyn Moulds

What was the source of your QC survey sample? Was it a CAP survey? You need to find out the source of the anti-D used for the survey and how strong it was by other methodologies. marilyn m

Just a few comments on the above case. There are NO commercial reagents licensed in the US that are human source; they are all monoclonal. Secondly, I would like to know how strong the reactions in the tube were with the Anti-A and Anti-B reagents? Were they also Ortho reagents or from a different manufacturer? Also, did the cells give any negative reactions in the tube with any other reagent, like a monoclonal control for the Rh (in the case of the ImmucorGamma reagents there is a Clone Control that is a dilutent used in the Anti-D reagent). Washing the cells should have eliminated the reactions in the tube unless the cells spontaneously agglutinate in the diluents used for the reagents (like due to pH). I assume the screening and autologous control were negative? Sorry for the questions. Marilyn M

If you order The Blood Group Antigen Facts Book, you should order the Second Edition. It is available at http://books.elsevier.com/factsbooks on the web. Marilyn

PS: sorry, I forgot to put the i in indianinitiative (in the initiative part). I should have proofread before I posted it. www.indianinitiative.org. Marilyn

Two other good sites, if you have not already been on them are: www.indianinitative.org which has some great lectures and case studies, and www.sbbpocketbook.com which has information on a great book for Blood Group Antigens and Antibodies book that is very inexpensive ($25) and also on a super Education Fund for students. Also, might I recommend the ARC journal Immunohematology that comes out 4 times a year and is free to SBB students and is very low cost also for a year's subscription, web site www.redcross.org/pubs/immuno. Marilyn M PS Ignore this e-mail if you are one of the lucky ones to have been on these web sites.

HTLA is a term we should avoid using and certainly an antibody should not be called this just because it has a high titer, especially in gel. There are antibodies that can give a high titer and low avidity and be clinically significant; ie anti-Yta, -Hy, -Doa, etc. I think the approach to giving crossmatch compatible in gel is a good way to obtain blood for patients when clinically significant antibodies have been ruled out. BUT, when there are NO negative cells in gel and the autologous control is negative, I would hesitate to call the antibody an HTLA. The sample needs to be sent to a Reference Lab that can determine a specifiity for the antibody. Marilyn M

You need to get a real good history on the patient, especially previous and/or recent transfusions. If the patient has not been recently transfused, then you have a warm reactive autoantibody and can do a ZZAP autoadsorption. If not, then adsorptions with selected cells will need to be done. I might make a cautionary comment about PEG adsorptions. There are several papers listing the limitations for PEG adsorptons where weak antibodies have been missed by this technique. We never started using it in my days at Gamma because of this. We were one of the first labs to write a response to the first Letter to the Editor of Transfusion on this subject. Marilyn M PS If you are interested in the references I can get them for you.

Dear Jeff: I just noticed on my posting of last week that I had answered Rashim's questions but that I had asked him instead of you whether you sent your anti-K to the manufacturer of the Echo? Also, I just remembered another fact about anti-K, and I will have to find the reference for this too, but in the literature there are different examples of anti-K that do not react well or not at all in some types of LISS. Perhaps your antibody is nonreactive in solid phase, not because of the instrument, but because of the LISS addative that is used. I know that the cells used in gel are suspended in a LISS solution, but the formulation is different from the solid phase LISS. Maybe you could try and experiment and leave out the LISS in the solid phase testing and see what happens. Just another suggestion. Marilyn M

I have not had time to digest all the postings on this topic since I was last on, but one point I can comment on, is that Capture (Solid Phase) Echo uses indicator cells that are made using a monoclonal Anti-IgG (16H8) that detects all IgG subclass antibodies that are clinically significant; ie, IgG 1, IgG 2 and IgG 3. The only IgG subclass antibodies not detected are IgG 4 are NOT clinically significant. On gel, I understand that IgM antibodies show up in gel if they are strong and cells/agglutinates get trapped in the top of the gel as the agglutinates can form as the serum and test cells are added, even before incubation, or it happens when centrifugation occurs and the temperature cools down. Lastly, Rashmi, have you sent any of your sample of anti-K to the manufacturer of the Echo? I believe it is always best to give the manufacturers, no matter who they are, a chance to test a sample that gives unusual results. Is this anti-K IgM? Have you done 2 ME or DTT-treatment of the serum/plasma to see if it does indeed have an IgG componcent? maybe I missed where you said this. My philosphy is that the antibodies are what are unusual and the FDA licensed reagents/products/instruments (especially in the US) are very good or FDA would not have licensed them. We are currently doing a study of three techniques (Tube, Gel and Solid Phase) and I can tell you right now that there are examples of anti-K, anti-E, etc that are detected by one technique and not the other two. It will be fun to see what our final results turn up. There is NO perfect technique. I rattled on. Have a good weekend everyone. Marilyn Moulds